“It's the Real Thing”
March 1, 2012
The Historian’s Desk By Lou Scalzo

Above: 962113 before restoration; Middle: Aluminum tub cockpit; Switches and gauges any air-cooled Porsche driver would recognize; Bottom: The 962’s flat six also looks pretty familiar, from the outside anyway.
962113 – 1986 Sebring Winner
What can be said about the 956/962? Plenty, of course, and over the years much has been published about Porsche’s most successful, racecar ever. With 129 overall wins in a 13 year span;– a record that is likely never to be duplicated– wins included the FIA Group C series, America’s IMSA, and the Japanese Sports Car Championship Series. The first win came in 1982 in 956-002, then a new racer out of the box, with drivers Jacky Ickx, and Derek Bell in Rothmans livery. The final win in came 1994 at Le Mans in the flat bottomed Dauer 962 built to GT1 rules, with drivers Mauro Baldi, Yannick Dalmas, Hurly Haywood and car owner Jochen Dauer.

The 956 was developed to replace the tube framed 936 by Porsche’s chief race engineer Norbert Singer, and was the first Porsche to utilize an aluminum monocoque chassis and ground effects undertray. What Singer discovered during wind tunnel testing was that the ground effects concept with a full width sports car didn’t work the same as in an open wheeled Formula 1 car. Singer learned that unlike a Formula 1 car, which developed downforce from the nose area, closed wheel sports cars developed downforce between the front and rear tires. Thus whenever the F1 style side skirts where added during early wind tunnel testing, the ground effect would be lost.

With this discovery, the shape of the tunnels became even more important, thus leading to angling the engine up towards the rear. The final prototype that emerged was one with a monocoque construction utilizing a double wishbone type suspension in the front, and behind the cockpit bulkhead was a detachable tubular subframe which supported the engine, transmission, and rear push rod suspension This was utilized in such a fashion to increase downforce of the tunnels by placing spring/shock units above the carefully designed under trays. Water radiators, and intercoolers where behind the cockpit doors in the car’s side pods, with a ramp designed to feed air to them in an efficient manner.

The engine was a 2.6 liter taken from original design for the cancelled Indy Car program, and was later used successfully on the 936. This motor used Bosch Motronic injection for the European Group C Series, which imposed a maximum fuel allocation during a race. The 956 design went on to be very successful, winning 5 consecutive World Sports Car titles from ’82 to ’86.

The Porsche 962 first appeared on American soil in 1984, featuring a revised 956 chassis that is 102mm longer than it’s earlier sibling 956. Developed to conform to IMSA head John Bishop for safety regulations which required the driver’s feet to be behind the front axle/suspension. The additional length was added between the area behind the front tire and in front of the driver’s door, and is the quickest way to visually distinguish the 2 cars. Another difference required by IMSA was that 962 have an air-cooled, 2-valve engine, compared to the 956’s 4-valve, “water boxer”.

The first time a 962 raced in American was in 1984 at the season opening Daytona 24 Hours, driven by Mario and Michael Andretti, where it failed to finish with engine and gearbox problems. Also discovered was that 2.8 liter engine was inadequate against Group 44 Jaguars, and Chevy powered March’s. (An interesting tidbit, was that the privateer Porsche teams where surprised and upset, thinking that they where to have exclusivity to the 962’s being delivered and raced in IMSA. However, it turned out that the Andretti’s where the only ones to ever race a factory backed 962’s in the IMSA series)

It was not until the mid-summer that Holbert Racing, with the famed Lowenbrau sponsored 962-103, would utilize a 3.2 liter, mechanically injected engine from a 935 along with the 956 “short tail” body work, that it would become a consistent winner. For the next several years in IMSA, it would be a Porsche 962 show, with 4 straight Daytona wins, 2 straight IMSA titles for Holbert Racing and 50 overall wins during it’s 11 year history.

“Have a Coke and a Smile”
The 962 featured in this month’s article is chassis #962113. Once again, Dave Brown from RennGruppe Motorsports in Lexington was gracious to invite me up to take a look at it while it is disassembled so that I could do a TR article from this unique perspective. It is being re-freshened for the Amelia Island Concourse in mid- March. This is one of the “early series” production cars, and was one of only 19 produced at the factory. It features a 5052 aluminum monocoque chassis with solid rivet construction, a steel roll cage riveted to the monocoque, and various machined steel bulkheads with suspension attach points. The car is built very much like aircraft construction of the same period, including aircraft electrical connectors and cannon plugs. Another feature is the 2 piece, ground effects undertray, consisting of a 3-foot aluminum section, and a 3-foot Kevlar section which connect in the front to the flat bottom monocoque tub. The tunnels continue under the rear suspension to the back end, creating the negative down force these cars are known for.

The engine is a 3.2 liter, air cooled with intercooled single KKK turbo, and a 5-speed manual 962 transmission. The brakes are an 8-caliper, 4-piston design, with conventional iron rotors. This car was originally purchased in 1985 by famed racer/owner Bob Akin to replace chassis #962-002, which was heavily damaged at the Road America race during the middle of the ‘85 race season.

This very successful #5 car was raced from mid-1985 thru 1987 under the sponsorship of Coke-Cola and Dominos Pizza. It competed in a total of 25 races, with 16 finishes, 9 retirements and 3 podium finishes including the overall win at the 1986 Sebring 12 hour, with drivers Bob Akin, Hans Stuck and Jo Gartner. (Unfortunately Jo Gartner later lost his life at Le Mans the same year when his Kremer 962’s right rear suspension broke at speed on the Mulsanne Strait)

Notable finishes in 1985 include 5th place At Sears Point, 5th place Columbus, Ohio and 6th place at the Daytona season finale. In 1986, #962-113 competed a full season, it’s best finishes include: 3rd place Miami Grand Prix, 1st place Sebring, 4th at Riverside, 2nd at Charlotte, 6th at Lime Rock, 4th at Watkins Glen and 4th at the Daytona season finale.

As for 1987, Bob Akin ran a reduced schedule, but was able to get some notable results including 6th at Sebring, 6th at Dayton, Ohio, 8th at Columbus, Ohio. At the end of the year #962-113 was retired for a newer 962 series chassis.

Due to the 962’s dominant racing success in IMSA’s GTP class in the mid ‘80s, series founder John Bishop attempted several times to limit the Porsche’s performance by either reducing the engine size, adding engine inlet restrictors or by adding weight. In the beginning in 1984, the maximum turbo engine size was 3.57 liters, with a minimum weight of 900kgs.

In 1985 maximum engine size was reduced to 3.5 liters. 1986 engine size was reduced to 3.2 liters and minimum weight was raised to 943kg. For 1987 the engine size was once again reduced to 3.0 liters, but the weight was also reduce to 930kg. 1988 saw the engine inlet restricted to 57mm, positioned within 50mm of the turbo charger. In mid season there was a revision for the air-cooled, single turbo cars, reducing weight to 924kg. By this time the “water boxer” 962 was also racing in the series to combat the new Nissan and Jaguar threat. These cars had a twin turbo 3.2 with 36mm restrictors.

By the late ‘80’s many of the privateer 962 teams continued to improve, and modify, their cars to remain competitive, including revisions to aerodynamics, bodywork, and mechanical improvements. Some teams went as far to build entirely new chassis of various materials such as carbon fiber, aluminum honeycomb, and stronger machined sections to improve rigidity. Those teams include:

• Joest Racing heavily modified a pair of 962’s to compete against Jaguar in IMSA, winning the 962’s final sprint race victory at Road America.
• The Kremer team built 11 carbon fiber tub cars, the 962CK6.
• John Thompson built 8 cars for Brun Motorsports, helping the team take second in the World Sports Car Championship 1987.
• Thompson also built 2 chassis for Obermaier Racing.
• Richard Lloyd Racing’s GTI engineering built 4 962 GTI’s, with an aluminum honeycomb chassis.
• Former factory driver Vern Schuppan, would also build 5 chassis, known at the TS962.
• Jochen Dauer, built a 962 street legal version, that qualified in the GT1 class and went on to win the 1994 Le Mans 24 hour.

The same was happening in America:

• Holbert Racing was making modifications to their chassis, renaming them 962HR series.
• Jim Busby contracted to Jim Chapman to build a more robust 962 monocoque.
• Dyson Racing used a Richard Lloyd chassis used for their 962DR-1 car.

Today the 956 and 962 live on, receiving legend status at historic racing events though out the world, providing the fans and owners with the kind of excitement often missing from today’s mundane sports car series. As time goes on that legend will only continue to grow.